Preparation of diacyloxydecadienes



Patented Feb. 16, 1954 PREPARATION OF DIACYLOXYDECADIENES Richard S.Urban, Philadelphia, Pa., assignor to Rohm & Haas Company, Philadelphia,Pa., a corporation of Delaware No Drawing. Application November 7, 1952,

Serial No. 319,408

This invention relates to-and has for its object-a process for thepreparation of mixtures of isomeric diacyloxydecadienes, which have thegeneral formulas,

H2CH2O C O R in which R, as above, is a hydrogen atom or a methyl orethyl group. The products of the reaction are iron chloride and amixture of isomeric diacyloxydecadienes having the above generalformulas.

The chloropentenyl esters which are essential reactants in the processof this invention are themselves prepared most conveniently by reactingbutadiene, hydrogen chloride, formaldehyde and either formic, acetic orpropionic acid in the presence of an acidic catalyst according to theprocess described in application for Letters Patent, Serial No. 3 9,407,filed of even date. That process gives rise to mixtures of isomericchloropentenyl esters which can be separated and then subjectedindividually to the process of this invention. Alternatively, mixturesof the isomeric esters can be employed in the instant process. In allcases, however, a mixture of the two isomeric diacyloxydecadienes isobtained, even when the starting material is a single chloropentenylester. Furthermore, the straight-chain diacyloxydecadiene (I, above) isalways formed in predominant amount.

The reaction of a chloropentenyl ester with finely divided iron iscarried out at a temperature from about 10 C.-or preferably 20 C.to therefluxing temperature of the reaction mixture. 7

' The use of a solvent is strongly recommended in order to facilitatethe reaction. Alcohols, in

general, are good solvents and of these ethanol appears to be mostsatisfactory. The use of other alcohols has been studied and it has beenfound that those containing one to seven carbon atoms, such as butyl,hexyl and benzyl alcohols, have an advantage over the higher alcohols inthat they can be more readily and cleanly separated from the reactionmixture by distillation. Other pre- 10 Claims. 260-488) ferred solventsinclude acetonitrile, dimethylformamide, propionitrile, butyronitrileand dioxane.

' The iron should be in a finely divided form. While coars metal filingscan be used, it is found that the yield of the diacyloxydecadienes isrelatively low and the yield of by-products is objectionably high.Therefore, in order to assure best'results, the iron should be so finelydivided as to pas through a No. U. S. Standard sieve. Since the oxidesof iron inhibit the reaction, it is most desirable that the metal bepure. Pyrophoric or hydrogen-reduced iron is recommended. At leastone-half mole of iron is employed per mole of chloropentenyl ester and,in fact, it is advantageous to use an excess of the order of 1o 50%. Themaximum amount of iron which can be used is limited only byconsideration of economy and mechanical operation.

- It has also been found that the rate of reaction can be increased andthe quantity of byproducts can be reduced when a finely divided metal ora salt of a metal which is below iron in the electromotive series isemployed. In View of the influence which these materials exert inconjunction with the iron coupling agent, they are called activators.

- The metals which are employed as such or in the form of salts togetherwith the iron and which are below iron in the electromotive series arecadmium, cobalt, nickel, tin, lead, palladium, copper, mercury, silver,gold and platinum. While all of these serve as activators in the instantinvention in conjunction with iron, it is preferred for reasons ofeconomy and eificiency to employ metallic copper, nickel, cobalt andmercury and the salts of these elements. All of the salts of the metalslisted above are operablethat is, the water-soluble or thewater-insoluble salts of organic and inorganic acids. Actually, thesalts of the strong inorganic acids, typified by chlorides, sulfates,nitrates and phosphate are preferred but others such as acetates,iormates,-

oxalates, benzoates and phthalates can be used. The amount of theactivator should be within the range of 1 to 15 %or preferably 2 to 8%-calculated as metal and based on the weight of the iron. Thus if a saltis employed, that amount of the salt is taken which provides 1 to 15% ofthe metal in the salt, based on the iron.

The reaction can be carried out under normal, super-, or sub-atmosphericpressure; but for reasons of efliciency it is preferred to employ normalor superatmospheric pressures.

The following examples, in which all parts are by weight, serve toillustrate the process of this invention.

Example 1 hours. The chloropentenyl formate was the iso- Y mer havingthe formula,

HCOOCH2CH2CH=CHCH2CT At the end of this time, thegrey color of thereaction mixture gradually turned green and heat- 7 ing was continuedfor three more hours. Then 200 parts of water was added. After cooling,the organic layer was taken up in 100' parts of ether. The ethersolution was washed with water, dried and fractionally distilled. Thefraction which boiled at 114-122 C./0.5 mm. weighed '36 partsand-{represented a 64% yield of a mixture of di..formoxydecadienesvwhose composition was con..- firmed by analysis. Thestraight-chain isomer, conforming to general formula I above, waspresent to the extent of about three times the amount of the otherisomer conforming to'general formula II, above. The product washydrogenated and saponified to yield 74.3% of the theoretical amount ofdecamethylene glycol (M. P. -32 0-) Example 2 24 parts ofhydrogen-reduced iron powder, 120. parts of acetonitrile and 0.5 part ofnickel sulfate was refluxed for five hours, extracted with ether andfractionally distilled. In this manner, a. 69.5% yield was obtained of amixture of diacetoxydecadieries which boiled at 120 155 C./0.6 mm. Hereagain the amount of straightchain decadiene predominated. Thecomposition of the product was confirmed by analysis and after beinghydrogenated and saponified, theproduct gave a 75% yield ofdecarhethylene glycol P. 7144 0.).

- Example 3 By the same procedure, a 69% yield of a mixture ofdipropoxydecadienes was obtained from chloropentenyl pro'pionate.

. Example 4 The procedure described in Example labove was followedseveral times with one exception, namely, that 74.3 parts (0.5 mole) ofa mixture of isomeric chloropentenyl formates, having the formulasHCOOCH2CH2CH=CHCH2C1 and I-ICOOCH2CH2CH(C1)CH=CH2 I was used. In allcases, the yield of the mixture of 'diformoxydecadienes was between 60and 80% shown above, the diacyloxdeca'dienes are readily converted intoglycols, predominantly de camethylene. glycol. The decamethylene glycolin turn is easily oxidized to sebacic acid. Thus, the products of thisinvention constitute an ex cellent source of dihydric alcohols anddicarboxylic acids, all of which are widely used for the manufacture oforganic plasticizers, alkyd resins and linear polyesters. Furthermore,the

4 diacyloxydecadienes and mixtures of their isomers can be saponified toproduce isomeric unsaturated glycols of the general formula,

HOCmHisOH particularly 3,7-decadiene-1,l0-diol, which are believed to benew compounds. v

I claim;

1. A process for preparing a mixture of isomeric diacyloxydecadieneshaving the formulas,

a hydrogen atom, a methyl group and an ethyl group, which comprisesreacting a chloropentenyl i ester of the formula,

RCOOCsHaCI in which R. has the significance described above, in thepresence of a solvent for the chloropentenyl ester, with finely dividediron at a temperature from 10 C. to the refluxing temperature of thereaction mixture, said iron being present- U. S. Standard sieve.

: formatewithfinely divided iron at a. temperatu'reI from 10 C. to therefluxing temperature of the, reaction mixture,-,said iron being presentin an amount equal to at least one-half mole per mole 3. A process forpreparing a mixture of di acyloxydecadienes having the formulas,R-COOCH2-CH2CH=CHCHz-CH2-CH=CH-CHar-GHz-OGQR andRC0OCH2-CHz-CH=CH-CH2-CHOH=CH:

CHz-CH2O C O R in which R is a member of the class consisting of ahydrogen atom, a methyl group and an ethyl group, which comprisesreacting a chloropentenyl ester of the formula,

RCOOCsHBCl in which R has the significance described above with finelydivided iron at a temperature from 10 C. to the refluxing temperature ofthe reaction mixture in the presence of a solvent for thechloropenten'yl ester and an activator, said iron being present in anamount equal to at least H one-half mole per mole of saidchloropentenyl" ester and said activator being a member of theclassconsisting of (a) the metals below iron the electromotive series and (b)the salts of said metals and strong inorganic acids and said activatorbeing present in such an amount as to pro-- vide metal based on theweight of said iron.

4. A process for preparing a mixture-of diformoxydecadienes having theformulas no 0 o CH2CH2CH=CHCH2CH2CH=CHCHICH2O O OH and EC 0o'cm'cmerb'oncnicncrboni meteor the formula, Hcooqimcl in'the presenceof a solvent for the chloropentenyl which comprises reacting achloropentenyl forof said chloropenten'yl formate.

5. A process for preparing a mixture of diacetoxydecadienes having theformulas,

which comprises reacting a chloropentenyl acetate of the formula,

CHsCOOCsHsCl in the presence of a solvent for the chloropentenyl acetatewith finely divided iron at a temperature from C. to the refluxingtemperature of the reaction mixture, said iron being present in anamount equal to at least one-half mole per mole of said chloropentenylacetate.

6. A process for preparing a mixture of dipropoxydecadienes having theformulas, CHaCHzCOOCHeCHzfiJH oHornomoH CHCHzCHzOCOCHzCH: and

CH3CH2COOOHzCHzCH=CHCHzCHCH=CH2 HzCHzOCOCHzCHx which comprises reactinga chloropentenyl propionate of the formula,

CI-IsCHzCOOC'sI-IaCl in the presence of a solvent for the chloropentenylpropionate with finely divided iron at a temperature from 10 C. to therefluxing temperature of the reaction mixture, said iron being presentin an amount equal to at least one-half mole per mole of saidchloropentenyl propionate.

7. As a new composition of matter, a mixture of isomericdiacyloxydecadienes having the formulas,

in which R, in all occurrences, is the same member of the classconsisting of a hydrogen atom, a methyl group and an ethyl group.

8. As a new composition of matter, a mixture of the isomericdiformoxydecadienes having the formulas,

HO O O CHnCH2CH=CHCH2CH2CH=CHCH2CH2O O OH and HC 0 0CHQGHZCH=CHCH2CHCH=CH2 CHzCHzO C OH 9. As a new composition of matter, amixture of the isomeric diacetoxydecadienes having the formulas CHaC O OCHZCHQCH=CHCH2OH2CH=CHCH2OH2O COCH; and

CH3) 0 O CH2CH2CH=CHCH2CHCH=CH2 CH2CH2O C OCH:

10. As a new composition of matter, a mixture of the isomericdipropoxydecadienes having the formulas CHsCHaC O O CHzCHzCH HCHaCHzCHHCHnCHaOC O CHsCHs and CHaCHaC O O CHzCHzCH=CHCH2CHCH=CHz CHzCHzO COCHzCHa RICHARD S. URBAN.

No references cited.

1. A PROCESS FOR PREPARING A MIXTURE OF ISOMERIC DIACYLOXYDECADIENESHAVING THE FORMULAS,